Research - Dr. Kirsten Leiss
The plant–herbivore resistance group, which I am heading, contributes to the development of durable and sustainable pest management. To do so we conduct research into host plant resistance from an ecological point of view. Utilizing the plants own defenses forms an essential part of economic, environmental and health benefits not only for farmers but to society in general. This mission is given from by working in a (1) performance orientated (2) independent and (3) and open manner. These three core values also characterize our team members. Enthusiastic and independent, but performance orientated researchers who are open minded to knowledge transfer and co-laborations. We currently work on the following projects:
- A metabolomics resistance test: STW, Suzanne Kos (PhD)
This research is aimed at developing a metabolomic resistance test, based on Nuclear Magnetic Resonance Spectroscopy (NMR), facilitating a high throughput screening of chemical host plant resistance. We will use chrysanthemum one of the most important ornamentals grown in the Netherlands and its three main pests: western flower thrips (Frankliniella occidentalis), celery leafminer (Liriomyza trifolii), and two-spotted spider mite (Tetranychus urticae) as a model. The metabolomic profiles of resistant and susceptible varieties will be compared to identify candidate compounds involved in resistance. The candidate compounds will then be validated with in-vitro bioassays. Using multivariate statistic, models will be developed to predict resistance based on the secondary metabolite patterns. The end results of this project is a high throughput resistance test, based on NMR to substitute time consuming and costly in -vivo resistance bioassays.
- Thrips resistance in tomatoes: ERA-NET Plant Genomics, Mohammad Mirnezhad (PhD), Roman Romero-González (PhD)
The objective of this project is developing tomato lines resistant to western flower thrips (Frankliniella occidentalis) by increasing natural levels of chlorogenic acid (CGA) by way of genetic engineering. To achieve this the natural variation of CGA in tomatoes is explored, the genetics behind CGA identified, the relationship of CGA biosynthesis to other primary and secondary metabolite pathways is studied, the understanding of the role of CGA in thrips resistance is increased, in particular possible synergy of CGA with other (phenolic) compounds and the activity of various cinnamic esters against thrips is determined.
- The importance of variation of pyrrolizidine alkaloids in plant defense of Senecio: Tri Rini Nuringtyas (PhD)
This project intends to study the origin and role of the diversity of pyrrolizidine alkaloids (PAs) and its importance for defense against generalist herbivores, such as the thrips Frankliniella occidentalis and the caterpillar Spodoptera exigua. Diversification of PAs will be studied using metabolomics, specifically applying surface and vacuole NMR. The role of individual PAs and PAs in mixtures, to study potential synergistic effects, will be explored by using in-vitro bioassays and insect cell cultures.
- Green Crop Protectants: EUROSTARS, Dinar Sari Cahyaningrum Wahyuni (PhD)
The aim of this project is to develop novel crop protectants from natural plant origin. It is focused on the large scale screening of plant extracts by NMR-metabolomics and bio-guided fractionation coupled with herbivore bioassays.
- Healthy and sustainable carrots: Rita Rakhmawati (PhD)
The aim of this project is to develop carrots resistant to herbivores which at the same time offer an additive human health value. Phenols are secondary metabolites implicated to be involved in resistance to herbivores as well as being antioxidants implicated in human cancer, cardiovascular and Alzheimer diseases as well as diabetes. Carrots are rich in phenols. Applying an eco-metabolomic approach the metabolomic profiles of herbivore resistant and susceptible carrots will be compared to identify candidate compounds involved in herbivore resistance. As herbivores the pests western flower thrips (Frankliniella occidentalis) and the carrot root fly (Psila rosae) will be used. Subsequently, the candidate compounds will be tested on their effect on human health using human cell lines and zebrafish models. Eighty-four cultivated and wild carrots accessions are available, which currently are used to construct a genetic map. Promising candidate compounds can thus be linked to the corresponding genes.
- Metabolic profiling of phenols in crops: Combining herbivore resistance with benefits for human health
(Gabriele Cristofori (MSc), Rosalinda van Steenis (BSc)
In this project the metabolomic basis of thrips (Franklinella occidentalis) and aphid (Myzuz persicae) resistance in crops rich in phenols, such as carrots and sweet pepper will be investigated using NMR. Phenols are secondary metabolites implicated to be involved in resistance to herbivores as well as being antioxidants implicated in human cancer, cardiovascular and Alzheimer diseases as well as diabetes.
- The role of phenolics in resistance to Phytophthora: Casia Lukasiewicz (BSc)
This research is designed to study the effects of phenols singly and in combination on the growth of different Phytophtohora species using in-vivo and in-vitro tests.
